Epidemiology characterization and risk factors of brucellosis among older rural populations in northwest China.

Brucellosis causes significant economic damage and public health problems in northwest China. The older rural population is considered a high-risk group. However, the epidemiological characteristics and risk factors for brucellosis in this population remain unclear. This study investigated these factors within this high-risk group by performing a cross-sectional study in five townships of Wuwei City, Gansu Province. Cases were screened via rose Bengal and serum plate agglutination tests. Risk factors were evaluated using a standard questionnaire form. This study included 1074 participants aged >50 years. Among them, 15 (1.4%) tested positive for Brucella. The most common symptoms were arthralgia/myalgia (n=5, 33.3%), and 10 (66.7%) cases were asymptomatic. Raising lambs artificially (odds ratio, 4.7; 95% CI, 1.3-17.0; P=0.02) increased the risk of brucellosis. The results indicated a high proportion of asymptomatic brucellosis in this group. Raising lambs artificially is a risk factor for brucellosis. The surveillance and health education of brucellosis for older rural populations in endemic areas of northwest China should been attention.